The use of color is of great significance to the appearance and usability of web interfaces. However, visually impaired people have always been ignored in web interface design in terms of color scheme. Therefore, it is necessary to study their difficulties while browsing web pages and accessing to information. By means of enumerating the color barriers, this paper summarizes the principles of how to use color in the web interface design for visually impaired people. It is expected that the proposed principles would benefit such people who conduct web interface design while being aware of the needs of visually impaired people.